Question

in a cladogram, what occurs at a node? a derived trait appears. an ancestor dies. the cladogram ends. evolution is stopped.

Explanation:

A cladogram is a diagram used in evolutionary biology to show relationships between organisms. Nodes in a cladogram represent the most recent common ancestor of the organisms that branch off from it, and at each node, a derived (new) trait that distinguishes the descendant groups from the ancestor appears. The other options are incorrect: an ancestor dying is not what a node represents, a cladogram doesn't end at a node (nodes are internal points), and evolution doesn't stop at a node.

Answer:

A. A derived trait appears